unsetenv
Syntax
Description
Examples
Create and Test Environment Variable
Create environment variable myVar
, and then check that it exists.
setenv("myVar","myValue"); isenv("myVar")
ans = logical
1
Remove myVar
, and then check that it no longer exists.
unsetenv("myVar"); isenv("myVar")
ans = logical
0
Create and Test Multiple Environment Variables
Create multiple environment variables, and then check that they exist.
setenv(["Var1" "Var2" "Var3" "Var4"],["Val1" "Val2" "Val3" "Val4"]); isenv(["Var1" "Var2"; "Var3" "Var4"])
ans = 2x2 logical array
1 1
1 1
Remove two of the environment variables using unsetenv
, and then check that they no longer exist.
unsetenv(["Var1" "Var4"]); isenv(["Var1" "Var2"; "Var3" "Var4"])
ans = 2x2 logical array
0 1
1 0
You can also remove environment variables using setenv
with missing
. Change the value of one environment variable and remove another.
setenv(["Var2" "Var3"],["ValB" missing]); isenv(["Var1" "Var2"; "Var3" "Var4"])
ans = 2x2 logical array
0 1
0 0
Input Arguments
varname
— Environment variable names
string scalar | character vector | string array | cell array of character vectors
Environment variable names, specified as a string scalar, character vector, string array, or cell array of character vectors.
Example: "PATH"
Version History
Introduced in R2022bR2023a: Remove multiple environment variables
Remove multiple environment variables by using unsetenv
with a string
array or cell array of character vectors as input.
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